Quick-release lens clamp pad assembly for use in eyeglass lens processing

ABSTRACT

A lens pad is provided for use on a lens clamp. The lens pad comprises a lens-engaging surface which, in turn, has a lens-facing recess located substantially centrally thereon. The lens-engaging surface thus is annular. Alternatively, the lens-engaging surface is more resilient toward a center thereof than toward a periphery thereof. Forces exerted by the lens pad against a surface of a lens when the lens pad is pressed against the surface therefore are less concentrated than such forces would be if the lens-engaging surface had no recess or variation in resiliency. Also provided is a clamp pad assembly. The clamp pad assembly includes a lens pad and a rotatable body for rotatably connecting the lens pad, at least indirectly, to a clamp arm. The clamp pad assembly also may include a swivel member which is pivotally mounted to the rotatable body for rotation therewith and for pivoting with respect thereto, in which case, the lens pad is mounted to the swivel member for rotation and pivoting therewith. The clamp pad assembly also may include a quick-release system capable of frictionally connecting the rotatable body to the clamp arm. The quick-release system permits quick removal and replacement of the clamp pad assembly for purposes of repair, changing lens pad configurations, changing lens pad sizes, and the like.

[0001] This is a Non-Provisional application of Provisional applicationSer. No. 60/112,568 filed on Dec. 16, 1998, and entitled Quick-ReleaseLens Clamp Pad Assembly for Use in Eyeglass Lens Processing.

BACKGROUND OF THE INVENTION

[0002] The present invention relates to a quick-release lens clamp padassembly for use in eyeglass lens processing. The quick-release clamppad assembly is particularly useful in the context of lens edging,although it is understood that the invention is not limited to thatparticular context.

[0003] Eyeglass lenses which carry anti-reflective coatings are becomingincreasingly popular. In the past, however, when such lenses have beensubjected to processing (e.g., during edging for purposes of adaptingthe lenses to a particular eyeglass frame or during other processingwhere the lens is held by its center), there has been a tendency tocrack, craze or otherwise deteriorate the anti-reflective coating. Suchdeterioration has been found to occur as a result of the pressureexerted on the coating(s) when such lenses are clamped at theirrespective centers. There is consequently a need in the art for a lensclamp capable of holding lenses for edge or near-edge processing, whichclamp also avoids or at least reduces the possibility of damage toanti-reflective coatings.

[0004] Another recent trend in the eyeglass industry is for the lensesof eyeglasses to be smaller in diameter. The latter trend is based atleast partially on recent changes in fashion.

[0005] While some people accept such changes in fashion, others resist.There is consequently a need for lens processing devices which areeasily adaptable to avoid damage to anti-reflective coatings and whichalso are adaptable to processing of lenses of various diameters,including the types of lenses which are referred to in the eyeglassindustry as “half-eye” lenses.

[0006] There also is a need in the art for a lens clamp pad assemblywhich can be used to secure a lens in place, and which also providesquick-release capabilities, whereby the lens clamp pad assembly can beeasily replaced with an identical, a similar, or a different lens clamppad assembly.

SUMMARY OF THE INVENTION

[0007] A primary object of the present invention is to provide a lensclamp capable of holding lenses for edge or near-edge processing, whichclamp also avoids or at least reduces the possibility of damage toanti-reflective coatings.

[0008] Another object of the present invention is to provide a lensclamp which easily adapts a lens processing device to avoid damage toanti-reflective coatings and which also adapts the lens processingdevice for processing of lenses of various diameters, including thetypes of lenses which are referred to in the eyeglass industry as“half-eye” lenses.

[0009] Still another object of the present invention is to provide alens clamp pad assembly which can be used to secure a lens in place, andwhich also provides quick-release capabilities, whereby the lens clamppad assembly can be easily replaced with an identical, a similar, or adifferent lens clamp pad assembly.

[0010] To achieve these and other objects, the present inventionprovides a lens pad for use on a lens clamp. The lens pad comprises alens-engaging surface. The lens-engaging surface has a lens-facingrecess located substantially centrally on the lens-engaging surface,whereby the lens-engaging surface is annular.

[0011] The present invention also provides a lens pad for use on a lensclamp, wherein the lens pad comprises a lens-engaging surface which ismore resilient toward a center thereof than toward a periphery thereof.Forces exerted by the lens pad against a surface of a lens when the lenspad is pressed against the surface therefore are less concentrated thansuch forces would be if the lens-engaging surface had no variation inresiliency.

[0012] Also provided by the present invention is a clamp pad assembly.The clamp pad assembly includes a lens pad and a rotatable body forrotatably connecting the lens pad, at least indirectly, to a clamp arm.The lens pad comprises a lens-engaging surface. The lens-engagingsurface has a lens-facing recess located substantially centrally on thelens-engaging surface, whereby the lens-engaging surface is annular.

[0013] The present invention also provides a clamp pad assembly having alens pad and a rotatable body for rotatably connecting the lens pad, atleast indirectly, to a clamp arm, wherein the lens pad comprises alens-engaging surface which is more resilient toward a center thereofthan toward a periphery thereof. Forces exerted by the lens pad againsta surface of a lens when the lens pad is pressed against the surfacetherefore are less concentrated than such forces would be if thelens-engaging surface had no variation in resiliency.

[0014] Also provided by the present invention is a clamp pad assemblycomprising a lens pad, a rotatable body, and a swivel member. Therotatable body is for rotatably connecting the lens pad, at leastindirectly, to a clamp arm. The swivel member is pivotally mounted tothe rotatable body for rotation therewith and for pivoting with respectthereto. The lens pad is mounted to the swivel member for rotation andpivoting therewith.

[0015] The present invention also provides a clamp pad assemblycomprising a lens pad, a rotatable body, and a quick-release system. Therotatable body is for rotatably connecting the lens pad, at leastindirectly, to a clamp arm. The quick-release system is capable offrictionally connecting the rotatable body to the clamp arm.

[0016] Also provided by the present invention is a clamp pad assemblycomprising a shaft, an O-ring in each of at least one O-ring groove ofthe shaft, a bearing, a rotatable body, a swivel member, and a lens pad.The shaft has first and second portions spaced longitudinally along theshaft. The first portion has at least one circumferential O-ring groove.An O-ring(s) is (are) provided in the O-ring groove(s), the O-ring(s)being resilient so that insertion of the first portion into a clamp armopening causes compression of the O-ring(s) and over-ridable frictionalretention of the first portion of the shaft in the opening of the clamparm. The bearing is located against the second portion of the shaft. Therotatable body is mounted to the bearing for rotation with respect tothe shaft. The swivel member is pivotally mounted to the rotatable bodyfor rotation therewith and for pivoting with respect thereto. The lenspad is mounted to the swivel member for rotation and pivoting with theswivel member.

[0017] The above and other objects and advantages will become morereadily apparent when reference is made to the following descriptiontaken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1 is an exploded cross-sectional view of clamp pad assemblyaccording to a preferred embodiment of the present invention.

[0019]FIG. 2 is a cross-sectional view of the assembled clamp padassembly shown in FIG. 1, when mounted on a first preferred clamp of anedging apparatus.

[0020]FIG. 3 is a cross-sectional view of the assembled clamp padassembly shown in FIG. 1, when mounted on a second preferred clamp of anedging apparatus.

[0021]FIG. 4 is a cross-sectional view of an alternative embodiment ofthe clamp pad assembly shown in FIG. 2, when mounted on the firstpreferred clamp shown in FIG. 2.

[0022]FIG. 5 is a cross-sectional view of the alternative embodimentshown in FIG. 4, when mounted on the second preferred clamp shown inFIG. 3.

[0023]FIG. 6 is an exploded cross-sectional view of a clamp pad assemblyaccording to a second embodiment of the present invention.

[0024]FIG. 7 is a cross-sectional view of the assembled clamp padassembly shown in FIG. 6, when mounted on the first preferred clamp ofan edging apparatus.

[0025]FIG. 8 is a cross-sectional view of the assembled clamp padassembly shown in FIG. 6, when mounted on a second preferred clamp of anedging apparatus.

[0026]FIG. 9 is a cross-sectional view of an alternative embodiment ofthe clamp pad assembly shown in FIG. 7, when mounted on the firstpreferred clamp shown in FIG. 7.

[0027]FIG. 10 is a cross-sectional view of the alternative embodimentshown in FIG. 9, when mounted on the second preferred clamp shown inFIG. 8.

[0028]FIGS. 11, 12, and 13 are rear, side, and front views,respectively, of a shaft which is used in both the first and secondembodiments shown in FIGS. 1 and 6.

[0029]FIGS. 14 and 15 are cross-sectional and front views, respectively,of a rotatable body which is used in the first embodiment shown in FIG.1.

[0030]FIGS. 16 and 17 are rear and cross-sectional views, respectively,of a swivel member which is used in the first embodiment shown in FIG.1.

[0031]FIGS. 18, 19, and 20 are front, cross-sectional, and rear views,respectively, of a replaceable pad which is used in the first embodimentshown in FIG. 1.

[0032]FIGS. 21, 22, and 23 are front, cross-sectional, and rear views,respectively, of a replaceable pad which is used in the secondembodiment shown in FIG. 6.

[0033]FIGS. 24 and 25 are rear and cross-sectional views, respectively,of a swivel member which is used in the second embodiment shown in FIG.6.

[0034]FIGS. 26, 27, and 28 are rear, cross-sectional, and front views,respectively, of a rotatable body which is used in the second embodimentshown in FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] The present invention will be described hereinafter in theexemplary context of an edging apparatus (e.g., an apparatus whichprovides edging of a lens for purposes of adapting the lens to aparticular eyeglass frame). An exemplary edger is shown in Wagner, U.S.Pat. No. 5,158,422, assigned to the assignee hereof, the disclosure ofwhich is incorporated herein by reference. It is understood, however,that the invention is not limited to use in connection with an edgingapparatus.

[0036]FIG. 1 is an exploded cross-sectional view of a clamp pad assembly10 according to a preferred embodiment of the present invention. Theclamp pad assembly 10 includes two O-rings 12, a shaft 14, an O-ring 15which is, in diameter, larger than the O-rings 12, a thrust bearing 16,a rotatable body 18, a swivel member 20, a fastener 22, and acounterbored pad 24.

[0037] The O-rings 12 and 14 preferably are made of rubber, syntheticrubber, or any other suitably resilient material. The shaft 14 androtatable body 18 preferably are made of stainless steel or the like.The swivel member 20 preferably is made of brass or the like, and thecounterbored pad 24 preferably is made of rubber, synthetic rubber, orany other suitably resilient material. While the foregoing materials arepreferred, it is understood that the invention is not limited toembodiments which use any or all of the foregoing exemplary materials.

[0038]FIG. 2 is a cross-sectional view of the assembled clamp padassembly 10. In FIG. 2, the clamp pad assembly 10 is shown mounted on afirst preferred clamp arm 26 of an edging apparatus. While the entireedging apparatus is not shown, such edging apparatuses are known. Oneexample of such a lens edging apparatus is-disclosed in U.S. Pat. No.5,158,422, the contents of which are incorporated herein by reference,with the clamp arm 216 therein corresponding to the clamp arm 26 hereof.

[0039] During an edging operation, the lens, which is to be subjected tothe edging operation, is rotatably held between two clamping members.The clamp pad assembly 10 and the clamp arm 26 can be usedadvantageously to define one of the clamping members. The clamp padassembly 10 and clamp arm 26 preferably define the clamping member whichis axially movable to selectively release or secure the lens in place.The clamp pad assembly 10 is provided on the axially movable clampingmember to avoid damage to the lens when the lens is clamped in place.

[0040] As shown in FIG. 2, the O-rings 12 circumferentially surround theshaft 14. Recesses 30 are provided in the shaft 14 to accommodate theO-rings 12, as best shown in FIG. 1. The shaft 14 has a portion 32 ofsmaller diameter than a portion 34. The O-rings 12 are mounted about theportion 32 of smaller diameter.

[0041] The portion 34 of larger diameter is where the larger O-ring 15is mounted. The larger O-ring 15 is accommodated in a suitablydimensioned recess 36 which circumferentially surrounds the region 34 ofthe shaft 14.

[0042] As shown in FIG. 2, the portion 32 of smaller diameter fitssnugly into a hole 40 in the clamp arm 26. When the portion 32 ispressed into the hole 40, the O-rings 12 are compressed and provide apress-fit retention effect, which keeps the clamp pad assembly 10secured to the arm 26. Notably, this press-fit retention effect can bemanually or otherwise overcome by pulling axially on the clamp padassembly 10. A quick-release arrangement therefore is achieved. Theclamp pad assembly 10 can be secured easily to the arm 26 by merelypressing the portion 32 into the hole 40, and can be removed easily fromthe arm 26 by merely pulling on the assembly 10 until the portion 32slides out from the hole 40. Such a quick-release arrangementadvantageously facilitates rapid removal, servicing, repair and/orreplacement of the clamp pad assembly 10. The replacement advantageouslycan be performed using an identical assembly 10, a reconditionedassembly 10, a different assembly 10 (e.g., different in size, shape, orotherwise), or a new assembly 10 which is the same as the replacedassembly was when new.

[0043] If it becomes desirable to forego the quick-release arrangement,a second fastener 41 (e.g., a #6-32 FHSC screw which is 0.375 inch long)can be inserted through a suitable opening in the arm 26 and can bethreadedly received by the shaft 14, as best shown in FIG. 2. Theillustrated embodiment therefore is easily adaptable to the particularneeds of each user.

[0044] The shaft 14 also includes a race 38 about which the thrustbearing 16 is mounted. The thrust bearing 16 provides an interfacebetween the shaft 14 and the rotatable body 18, which permits rotationof the rotatable body 18 with respect to the rotationally stationaryshaft 14. In particular, the thrust bearing 16 and the race 38 areaccommodated in a thrust bearing pocket 42 of the rotatable body 18. Apocket 44 of larger diameter than the pocket 42 also is provided in therotatable body 18. The pocket 44 of larger diameter accommodates theportion 34 of larger diameter and the O-ring 15. The rotatable body 18also includes a through-hole 46 which allows the fastener 22 to passthrough the rotatable body 18 and to be threadedly received by aninternally threaded bore 48 of the shaft 14.

[0045] The rotatable body 18 further includes a swivel pocket 50. Theswivel pocket 50 accommodates a similarly shaped portion of the swivelmember 20. The swivel member 20 rotates with the rotatable body 18 whenthe rotatable body 18 rotates. A through-hole 52 is provided in theswivel member 20. The fastener 22 passes through the through-hole 52,and after passing through the through-hole 46 of the rotatable body 18,the fastener 22 threadedly engages the shaft 14. Preferably, thefastener 22 is threadedly engaged into the shaft 14 and then is rotatedout (or loosened) by about one full turn to permit swiveling of theswivel member 20. A thread-locking compound (or tape) may be used tokeep the fastener 22 from further loosening. One example of such athread-locking compound is commercially available under the trademark“LOC-TITE”. The swiveling provided by the swivel member 20advantageously compensates for variations in the curvature of a lens(e.g., any angularity induced by prism). Compensation for asymmetriclenses is thereby provided.

[0046] Preferably, the fastener 22 has a flat head 54, a shank 56, and ashoulder 58 between the head 54 and the shank 56. The shoulder 58preferably has a diameter which progressively increases from the shank56 to the head 54.

[0047] After the fastener 22 is secured in place, the counterbored pad24 is applied to the swivel member 20. In particular, the counterboredpad 24 has a shank 60 which is accommodated and frictionally retained ina pad recess 62 of the swivel member 20. A shoulder 63 of thecounterbored pad 24 provides a transition to a head 64 of the pad 24.The head 64 is hollowed out to form a lens-center-facing circular recess66. The lens-center-facing recess 66 advantageously distributes pressingforces over a greater surface area than would be case without the recess66. In particular, pressing of the clamp pad assembly 10 against asuitably positioned lens causes the majority of the pressing forces tobe applied over the larger surface area defined by the annularlens-engaging surface 68 of the pad 24. The force per unit of surfacearea therefore is reduced because of the larger distribution of pressingforces. The larger distribution of pressing forces thereby serves toreduce or eliminate the detrimental effects on the lens and its coatingswhich might otherwise occur as a result of more concentrated pressingforces.

[0048] The advantages of the present recess 66 are realized regardlessof whether the pad 24 is applied against a concave, convex, orsubstantially flat surface of a lens. In situations where an annularlens block is adhesively attached to the opposite surface of the lens,the recess 66 advantagously causes the pad 24 to push the lens moredirectly against the block, with the pressing force distributed over agreater surface area.

[0049] While a counterbored pad 24 is shown as the exemplary way ofachieving the larger distribution of pressing forces, it is understoodthat similar results can be achieved using, for example, a compositelens engaging surface of discretely or progressively increasing rigiditytoward radially outer portions of the lens engaging surface. The presentinvention thus is not limited to the illustrated embodiment.

[0050] Advantageously, the frictional retention of the counterbored pad24 in the swivel member 20 facilitates replacement and/or repair of thepad 24. When the pad 24 wears out, for example, the pad 24 is pulled outfrom the swivel member 20 and is easily replaced or repaired. Since theclamp pad assembly 10 preferably is secured to the arm 26 using aquick-release arrangement, the replacement and/or repair of the pad 24can be achieved quickly and easily by either pulling out the pad 24alone or, if desired, by pulling out the entire clamp pad assembly 10and removing the pad 24 after removal of the entire clamp pad assembly10. The versatility provided by the illustrated arrangement representsyet another advantage of the present invention.

[0051] Of course, if replacement of the entire assembly 10 is moredesirable than replacement of the pad 24 alone, it is understood thatthe pad 24 can be secured permanently to the swivel member 18.Typically, however, the ability to remove the pad 24 will be preferred.

[0052]FIG. 3 is a cross-sectional view of the assembled clamp padassembly 10 shown in FIG. 1, when mounted on a second preferred clamp ofan edging apparatus. In the second preferred clamp, the clamp arm 26 hasan angled back side 28.

[0053]FIG. 4 is a cross-sectional view of an alternative embodiment ofthe clamp pad assembly shown in FIG. 2, when mounted on the firstpreferred clamp shown in FIG. 2. In the illustrated alternativeembodiment, the fastener 22 is shorter and therefore does not extendinto the shaft 14. In FIG. 2, the fastener 22 (e.g., a #6-32 FHSC screw)is about 0.625 inch long, whereas in FIG. 4, the fastener 22 is about0.375 inch long. The fastener 22 shown in FIG. 4, therefore, is notthreadedly received by the shaft 14, but rather is threadedly receivedby the clamp body 18. The O-ring 15 thus is primarily responsible forholding the assembly 10 together in the embodiment of FIG. 4.

[0054] Otherwise, the components which make up the assembly 10 in FIG. 4are substantially the same as their counterparts in FIG. 2. FIG. 5 is across-sectional view of the alternative embodiment shown in FIG. 4, whenmounted on the second preferred clamp shown in FIG. 3. Notably, theclamp arm 26 has an angled back side 28.

[0055]FIG. 6 is an exploded cross-sectional view of a clamp pad assembly10′ according to a second embodiment of the present invention. Thissecond embodiment shares many similar components to its counterpartshown in FIG. 1. The second embodiment differs, however, in that it isadapted for use on lenses (e.g., half-eye lenses) having smallerdimensions, especially smaller diametric dimensions (or lenses which areto be cut or edged to have smaller diametric dimensions). Thecounterbored pad 24 in FIG. 6 therefore has a smaller diameter than thatwhich appears in FIG. 1. A smaller lens engaging surface 68 therefore ispresented. Though the distribution of pressing forces tends to not be aslarge in the embodiment of FIG. 6 as that of the assembly 10 shown inFIG. 1, it nevertheless represents an improvement over the centrallyconcentrated pressing forces which result from other pad arrangements.

[0056] To compensate for the decrease in force distribution and theconsequent increase in force per unit length around the annularlens-engaging surface 68, when compared to the embodiment shown in FIG.1, the embodiment shown in FIG. 6 has a pad 24 with an increasedthickness between the shoulder 63 and the wall 70 of the recess 66. Thisincreased thickness eliminates (or at least significantly reduces) thelikelihood of failure (e.g., cracking) in response to the decreasedforce distribution. Of course, it is understood that the invention isnot limited to this exemplary way of compensating for the decreases andincreases in force distribution associated with the different sizes ofpads 24. Such compensation also can be achieved by using differentmaterials, reinforcement, and the like.

[0057]FIG. 7 is a cross-sectional view of the assembled clamp padassembly 10′ shown in FIG. 6, when mounted on the first preferred clampof an edging apparatus. The clamp arm 26 is again designated usingreference numeral 26. Notably, the quick-release arrangement provided bythe shaft 14, O-rings 12, and the arm 26 facilitates switching of theclamp pad assembly 10′ for the assembly 10 and vice versa.

[0058]FIG. 8 is a cross-sectional view of the assembled clamp padassembly 10′ shown in FIG. 6, when mounted on the second preferred clampof an edging apparatus. Notably, the angled back side 28 is present.

[0059]FIG. 9 is a cross-sectional view of an alternative embodiment ofthe clamp pad assembly shown in FIG. 7, when mounted on the firstpreferred clamp shown in FIG. 7. In the illustrated alternativeembodiment, the primary difference from the embodiment illustrated inFIG. 7 is that the fastener 22 is shorter and therefore does not extendas far into the shaft 14. Otherwise, the components which make up theassembly 10′ in FIG. 9 are substantially the same as their counterpartsin FIG. 7. FIG. 10 is a cross-sectional view of the alternativeembodiment shown in FIG. 9, when mounted on the second preferred clampshown in FIG. 8. Notably, the clamp arm 26 has the angled back side 28.

[0060]FIGS. 11, 12, and 13 are rear, side, and front views,respectively, of the shaft 14 which is used in both the first and secondembodiments shown in FIGS. 1 and 6. The shaft 14 preferably is about0.610 inch long, and at its widest part, preferably has a diameter ofabout 0.593 to 0.597 inch. Additional preferred dimensions are shown inthe drawings of the provisional application, the contents of which areincorporated herein by reference. While preferred dimensions and shapesare shown, it is understood that the invention is not limited to thepreferred dimensions and shapes. Variations from the preferreddimensions and shapes are contemplated and would fall well within thescope of the present invention.

[0061]FIGS. 14 and 15 are cross-sectional and front views, respectively,of the rotatable body 18 which is used in the first embodiment shown inFIG. 1. Preferably, the outside diameter of the rotatable body 18 isabout 0.875 inch. A preferred length of the rotatable body 18 is about0.690 inch. Additional preferred dimensions are shown in the drawings ofthe provisional application, the contents of which are incorporatedherein by reference. While preferred dimensions and shapes are shown, itis understood that the invention is not limited to the preferreddimensions and shapes. Variations from the preferred dimensions andshapes are contemplated and would fall well within the scope of thepresent invention.

[0062]FIGS. 16 and 17 are rear and cross-sectional views, respectively,of the swivel member 20 which is used in the first embodiment shown inFIG. 1. Preferably, the outside diameter of the swivel member 20 isabout 0.875 inch. The inside diameter preferably is about 0.482 inch atthe entrance to the pad recess 62 and progressively increases at a rateof about 3 degrees. This progressively increasing inside diameter of thepad recess 62 provides an enhanced grip on the shank 60 of the lens pad24 and more positively maintains a desired position of the shank 60 inthe swivel member 20. Preferably, the swivel member 20 has a length ofabout 0.392 inch. Additional preferred dimensions are shown in thedrawings of the provisional application, the contents of which areincorporated herein by reference. While preferred dimensions and shapesare shown, it is understood that the invention is not limited to thepreferred dimensions and shapes. Variations from the preferreddimensions and shapes are contemplated and would fall well within thescope of the present invention.

[0063]FIGS. 18, 19, and 20 are front, cross-sectional, and rear views,respectively, of the replaceable pad 24 which is used in the firstembodiment shown in FIG. 1. Preferably, the head 64 of the pad 24 has anoutside diameter of about 0.8 inch, and the shank 60 has an outsidediameter of about 0.5 inch. The pad 24 preferably is about 0.325 inchlong, with the head 64 accounting for about 0.125 inch of the 0.325 inchlength and the shank 60 accounting for the other 0.200 inch of the 0.325inch length. The recess 66 of the pad 24 preferably is about 0.08 inchdeep. Additional preferred dimensions are shown in the drawings of theprovisional application, the contents of which are incorporated hereinby reference. While preferred dimensions and shapes are shown, it isunderstood that the invention is not limited to the preferred dimensionsand shapes. Variations from the preferred dimensions and shapes arecontemplated and would fall well within the scope of the presentinvention.

[0064]FIGS. 21, 22, and 23 are front, cross-sectional, and rear views,respectively, of the replaceable pad 24 which is used in the secondembodiment shown in FIG. 6. Preferably, the pad in FIG. 6 has the samelength dimensions as the pad shown in FIG. 1 and the same shankdiameter, as well. The outside diameter of the head 64 of the pad 24 inFIGS. 6, 21, 22, and 23, however, is 0.650 inch. Also, the recess 66 ofthe pad 24 in FIGS. 6 and 21-23 preferably is about 0.067 inch deep atits deepest point. Additional preferred dimensions are shown in thedrawings of the provisional application, the contents of which areincorporated herein by reference. While preferred dimensions and shapesare shown, it is understood that the invention is not limited to thepreferred dimensions and shapes. Variations from the preferreddimensions and shapes are contemplated and would fall well within thescope of the present invention.

[0065]FIGS. 24 and 25 are rear and cross-sectional views, respectively,of the swivel member 20 which is used in the second embodiment shown inFIG. 6. Preferably, the outside diameter of the swivel member 20 inFIGS. 6, 24 and 25 is about 0.65 inch. The inside diameter preferably isabout 0.482 inch at the entrance to the pad recess 62 and progressivelyincreases at a rate of about 3 degrees. This progressively increasinginside diameter of the pad recess 62 provides an enhanced grip on theshank 60 of the lens pad 24 and more positively maintains a desiredposition of the shank 60 in the swivel member 20. Preferably, the swivelmember 20 has a length of about 0.392 inch (i.e. the same length as thatof the swivel member 20 in FIG. 1). Additional preferred dimensions areshown in the drawings of the provisional application, the contents ofwhich are incorporated herein by reference. While preferred dimensionsand shapes are shown, it is understood that the invention is not limitedto the preferred dimensions and shapes. Variations from the preferreddimensions and shapes are contemplated and would fall well within thescope of the present invention.

[0066]FIGS. 26, 27, and 28 are rear, cross-sectional, and front views,respectively, of the rotatable body 18 which is used in the secondembodiment shown in FIG. 6. Preferably, the outside diameter of therotatable body 18 in FIGS. 6 and 26-28 is about 0.65 inch. A preferredlength of the rotatable body 18 is about 0.6 inch. Additional preferreddimensions are shown in the drawings of the provisional application, thecontents of which are incorporated herein by reference. While preferreddimensions and shapes are shown, it is understood that the invention isnot limited to the preferred-dimensions and shapes. Variations from thepreferred dimensions and shapes are contemplated and would fall wellwithin the scope of the present invention.

[0067] The illustrated embodiments achieved several advantages overconventional clamp pads. The ability to quickly replace lens clamp padassemblies provides increased versatility and manufacturingefficiencies. One such efficiency is realized by a reduction in thedown-time which is usually required to replace a worn or otherwiseinappropriate clamp pad and/or related assembly.

[0068] While the advantages of the present invention typically will bemaximized by combining all of the advantageous aspects described above,it is understood that individual aspects can be used without the variousother advantageous aspects. The quick-release arrangement, for example,can be used with pads which lack the recess 66. The quick-releasearrangement also can be used to facilitate changes from assemblies whichcarry the pads with the recess 66 to those which carry the pads withoutthe recess, when the recess is not needed (e.g., when fragile coatingsare not applied to the lenses), and vice versa when the recess isneeded. The quick-release arrangement also can be used, with or withoutthe other advantageous aspects of the invention, to facilitate quickswitching between lens pad assemblies having lens pads of differentsizes. This, in turn, permits rapid adaptation of lens processingdevices to accommodate lenses having different sizes.

[0069] Likewise, the pads 24 with the recess 66 can be provided on aclamp pad assembly which does not include a quick-release arrangement.The removability of the pad 24 from the swivel member 18 also can beprovided with or without the quick-release arrangement and/orcounterbored pads 24.

[0070] While the present invention has been described with reference topreferred embodiments, it is understood that the invention is notlimited to the illustrated and described features. To the contrary, theinvention is capable of further modifications, usages, and/oradaptations following the general principles of the invention andtherefore includes such departures from the present disclosure as comewithin known or customary practice in the art to which the inventionpertains, and as may be applied to the central features set forth above,and which fall within the scope of the appended claims.

We claim:
 1. A lens pad for use on a lens clamp, said lens padcomprising a lens-engaging surface, said lens-engaging surface having alens-facing recess located substantially centrally on the lens-engagingsurface, whereby said lens-engaging surface is annular.
 2. The lens padof claim 1 , wherein said lens pad further comprises a shank and a head,said lens-engaging surface being disposed on said head, said head beingat least partially hollowed to define said lens-facing recess.
 3. Thelens pad of claim 2 , wherein said lens-facing recess is disposedsubstantially centrally in the lens-engaging surface on the head.
 4. Thelens pad of claim 2 , wherein said shank is shaped to facilitateinsertion of the shank into a pad recess, frictional retention therein,and removal of the lens pad out from the pad recess if the lens padbecomes excessively worn.
 5. The lens pad of claim 1 , wherein saidlens-engaging surface is made of a resilient material to avoid damage tolenses and coatings thereof.
 6. A lens pad for use on a lens clamp, saidlens pad comprising a lens-engaging surface which is more resilienttoward a center thereof than toward a periphery thereof, whereby forcesexerted by said lens pad against a surface of a lens when the lens padis pressed against said surface are less concentrated than such forceswould be if the lens-engaging surface had no variation in resiliency. 7.The lens pad of claim 6 , wherein said lens pad further comprises ashank and a head, said lens-engaging surface being disposed on saidhead.
 8. The lens pad of claim 7 , wherein said shank is shaped tofacilitate insertion of the shank into a pad recess, frictionalretention therein, and removal of the lens pad out from the pad recessif the lens pad becomes excessively worn.
 9. A clamp pad assemblycomprising: a lens pad; and a rotatable body for rotatably connectingthe lens pad, at least indirectly, to a clamp arm, said lens padcomprising a lens-engaging surface, said lens-engaging surface having alens-facing recess located substantially centrally on the lens-engagingsurface, whereby said lens-engaging surface is annular.
 10. The clamppad assembly of claim 9 , wherein said lens pad further comprises ashank and a head, said lens-engaging surface being disposed on saidhead, said head being at least partially hollowed to define saidlens-facing recess.
 11. The clamp pad assembly of claim 10 , whereinsaid lens-facing recess is disposed substantially centrally in thelens-engaging surface on the head.
 12. The clamp pad assembly of claim10 , wherein said rotatable body presents a pad recess to said lens pad,said shank being shaped to facilitate insertion of the shank into saidpad recess, frictional retention therein, and removal of the shank outfrom the pad recess if the lens pad becomes excessively worn.
 13. Theclamp pad assembly of claim 12 , further comprising a swivel memberconnected pivotally to said rotatable body, whereby compensation forasymmetric lenses is provided by pivoting of the swivel member and ofsaid lens pad with respect to said rotatable body during rotation ofsaid rotatable body, said pad recess being defined in said swivelmember.
 14. The clamp pad assembly of claim 9 , further comprising aswivel member connected pivotally to said rotatable body, said lens padbeing mounted to said swivel member, whereby compensation for asymmetriclenses is provided by pivoting of the swivel member and of said lens padwith respect to said rotatable body during rotation of said rotatablebody.
 15. The clamp pad assembly of claim 14 , wherein said rotatablebody is connected to a quick-release system capable of frictionallyconnecting said rotatable body to said clamp arm.
 16. The clamp padassembly of claim 15 , wherein said quick-release system includes: ashaft connected to said rotatable body, said rotatable body beingmounted to said shaft for rotation with respect thereto, said shafthaving at least one circumferential O-ring groove; and an O-ringdisposed in each of said at least one O-ring groove, said O-ring beingresilient such that insertion of said shaft into an opening in saidclamp arm causes compression of said O-ring and frictional retention ofsaid shaft in said opening, said frictional retention being selectivelyover-ridable to release said shaft from said clamp arm.
 17. The clamppad assembly of claim 9 , wherein said rotatable body is connected to aquick-release system capable of frictionally connecting said rotatablebody to said clamp arm.
 18. The clamp pad assembly of claim 17 , whereinsaid quick-release system includes: a shaft connected to said rotatablebody, said rotatable body being mounted to said shaft for rotation withrespect thereto, said shaft having at least one circumferential O-ringgroove; and an O-ring disposed in each of said at least one O-ringgroove, said O-ring being resilient such that insertion of said shaftinto an opening in said clamp arm causes compression of said O-ring andfrictional retention of said shaft in said opening, said frictionalretention being selectively over-ridable to release said shaft from saidclamp arm.
 19. The clamp pad assembly of claim 9 , wherein saidlens-engaging surface is made of a resilient material to avoid damage tolenses and coatings thereof.
 20. A clamp pad assembly comprising: a lenspad; and a rotatable body for rotatably connecting the lens pad, atleast indirectly, to a clamp arm, said lens pad comprising alens-engaging surface which is more resilient toward a center thereofthan toward a periphery thereof, whereby forces exerted by said lens padagainst a surface of a lens when the lens pad is pressed against saidsurface are less concentrated than such forces would be if thelens-engaging surface had no variation in resiliency.
 21. The clamp padassembly of claim 20 , wherein said lens pad further comprises a shankand a head, said lens-engaging surface being disposed on said head. 22.The clamp pad assembly of claim 21 , wherein said rotatable bodypresents a pad recess to said lens pad, said shank being shaped tofacilitate insertion of the shank into said pad recess, frictionalretention therein, and removal of the shank out from the pad recess ifthe lens pad becomes excessively worn.
 23. The clamp pad assembly ofclaim 22 , further comprising a swivel member connected pivotally tosaid rotatable body, whereby compensation for asymmetric lenses isprovided by pivoting of the swivel member and of said lens pad withrespect to said rotatable body during rotation of said rotatable body,said pad recess being defined in said swivel member.
 24. The clamp padassembly of claim 20 , further comprising a swivel member connectedpivotally to said rotatable body, said lens pad being mounted to saidswivel member, whereby compensation for asymmetric lenses is provided bypivoting of the swivel member and of said lens pad with respect to saidrotatable body during rotation of said rotatable body.
 25. The clamp padassembly of claim 24 , wherein said rotatable body is connected to aquick-release system capable of frictionally connecting said rotatablebody to said clamp arm.
 26. The clamp pad assembly of claim 25 , whereinsaid quick-release system includes: a shaft connected to said rotatablebody, said rotatable body being mounted to said shaft for rotation withrespect thereto, said shaft having at least one circumferential O-ringgroove; and an O-ring disposed in each of said at least one O-ringgroove, said O-ring being resilient such that insertion of said shaftinto an opening in said clamp arm causes compression of said O-ring andfrictional retention of said shaft in said opening, said frictionalretention being selectively over-ridable to release said shaft from saidclamp arm.
 27. The clamp pad assembly of claim 20 , wherein saidrotatable body is connected to a quick-release system capable offrictionally connecting said rotatable body to said clamp arm.
 28. Theclamp pad assembly of claim 27 , wherein said quick-release systemincludes: a shaft connected to said rotatable body, said rotatable bodybeing mounted to said shaft for rotation with respect thereto, saidshaft having at least one circumferential O-ring groove; and an O-ringdisposed in each of said at least one O-ring groove, said O-ring beingresilient such that insertion of said shaft into an opening in saidclamp arm causes compression of said O-ring and frictional retention ofsaid shaft in said opening, said frictional retention being selectivelyover-ridable to release said shaft from said clamp arm.
 29. A clamp padassembly comprising: a lens pad; a rotatable body for rotatablyconnecting the lens pad, at least indirectly, to a clamp arm; and aswivel member pivotally mounted to the rotatable body for rotationtherewith and for pivoting with respect thereto, said lens pad beingmounted to said swivel member for rotation and pivoting therewith. 30.The clamp pad assembly of claim 29 , wherein said lens pad comprises ashank, a head, and a lens-engaging surface disposed on said head. 31.The clamp pad assembly of claim 30 , wherein said swivel member presentsa pad recess to said lens pad, said shank being shaped to facilitateinsertion of the shank into said pad recess, frictional retentiontherein, and removal of the shank out from the pad recess if the lenspad becomes excessively worn.
 32. The clamp pad assembly of claim 29 ,wherein said rotatable body is connected to a quick-release systemcapable of frictionally connecting said rotatable body to said clamparm.
 33. The clamp pad assembly of claim 32 , wherein said quick-releasesystem includes: a shaft connected to said rotatable body, saidrotatable body being mounted to said shaft for rotation with respectthereto, said shaft having at least one circumferential O-ring groove;and an O-ring disposed in each of said at least one O-ring groove, saidO-ring being resilient such that insertion of said shaft into an openingin said clamp arm causes compression of said O-ring and frictionalretention of said shaft in said opening, said frictional retention beingselectively over-ridable to release said shaft from said clamp arm. 34.A clamp pad assembly comprising: a lens pad; a rotatable body forrotatably connecting the lens pad, at least indirectly, to a clamp arm;and a quick-release system capable of frictionally connecting saidrotatable body to said clamp arm.
 35. The clamp pad assembly of claim 34, wherein said quick-release system includes: a shaft connected to saidrotatable body, said rotatable body being mounted to said shaft forrotation with respect thereto, said shaft having at least onecircumferential O-ring groove; and an O-ring disposed in each of said atleast one O-ring groove, said O-ring being resilient such that insertionof said shaft into an opening in said clamp arm causes compression ofsaid O-ring and frictional retention of said shaft in said opening, saidfrictional retention being selectively over-ridable to release saidshaft from said clamp arm.
 36. The clamp pad assembly of claim 35 ,wherein said lens pad further comprises a shank, a head, and alens-engaging surface disposed on said head.
 37. The clamp pad assemblyof claim 36 , wherein said rotatable body presents a pad recess to saidlens pad, said shank being shaped to facilitate insertion of the shankinto said pad recess, frictional retention therein, and removal of theshank out from the pad recess if the lens pad becomes excessively worn.38. The clamp pad assembly of claim 34 , wherein said lens pad furthercomprises a shank, a head, and a lens-engaging surface disposed on saidhead.
 39. The clamp pad assembly of claim 38 , wherein said rotatablebody presents a pad recess to said lens pad, said shank being shaped tofacilitate insertion of said shank into said pad recess, frictionalretention therein, and removal of the shank out from the pad recess ifthe lens pad becomes excessively worn.
 40. A clamp pad assemblycomprising: a shaft having first and second portions spacedlongitudinally along the shaft, said first portion having at least onecircumferential O-ring groove; an O-ring in each of said at least oneO-ring groove, said O-ring being resilient so that insertion of saidfirst portion into a clamp arm opening causes compression of said O-ringand over-ridable frictional retention of the first portion of the shaftin the opening of the clamp arm; a bearing located against the secondportion of the shaft; a rotatable body mounted to the bearing forrotation with respect to the shaft; a swivel member pivotally mounted tothe rotatable body for rotation therewith and for pivoting with respectthereto; and a lens pad mounted to said swivel member for rotation andpivoting with the swivel member.
 41. The clamp pad assembly of claim 40, wherein said lens pad includes a lens-engaging surface and alens-facing recess located substantially centrally on the lens-engagingsurface, whereby said lens-engaging surface is annular.
 42. The clamppad assembly of claim 40 , wherein said lens pad includes alens-engaging surface which is more resilient toward a center thereofthan toward a periphery thereof, whereby forces exerted by said lens padagainst a surface of a lens when the lens pad is pressed against saidsurface are less concentrated than such forces would be if thelens-engaging surface had no variation in resiliency.